Does water use electricity? While pure water is not an electrical conductor, the process of getting clean water from its source to your tap, and treating it afterward, is incredibly energy-intensive. This interdependence is known as the “water-energy nexus,” where energy is needed for every step of the water cycle. This connection reveals the hidden electricity cost associated with every drop of water used.
Powering the Water Grid: Pumping and Treatment
The journey of municipal water begins with a significant electrical demand, primarily for movement and purification. Water must be extracted from its source, such as a reservoir, river, or aquifer, often requiring powerful pumps to lift and transport it over long distances to treatment facilities. This initial pumping and movement is typically the single largest consumer of energy within a utility’s operations.
Once at a facility, electricity is needed to run equipment for filtration and chemical disinfection. After distribution through vast piping networks, additional booster pumps are often required to maintain adequate pressure across different elevations. Water and wastewater utilities combined consume approximately 4% of the power in the United States, illustrating the scale of this energy requirement.
The energy cycle does not end at the drain; wastewater must also be collected and treated before being released back into the environment. Treatment plants use electricity for aeration, which pumps oxygen into the water to break down organic matter, and for sludge handling and final disinfection stages. In some operations, up to 90% of the energy consumed is dedicated solely to pumping the water.
The Biggest Energy Draw: Heating Water at Home
While the municipal infrastructure’s energy use is substantial, the largest water-related electricity expense happens inside the house. Heating water for showers, laundry, and dishwashing consumes a significant portion of total energy. Water heating accounts for 14% to 18% of a home’s total energy consumption, making it the second-largest utility cost after space heating and cooling.
Electric water heaters, boilers, and tankless systems require a substantial energy input to raise the temperature of cold water. A typical electric water heater may use between 3,500 and 5,500 watts when running, translating to 12 to 15 kilowatt-hours per day for an average household. This high energy demand is due to resistance heating, which converts electrical energy directly into thermal energy. The constant need to heat and reheat water stored in a tank contributes to this substantial energy draw.
The energy cost is compounded by factors like tank size, insulation quality, and the frequency of hot water use. Even in homes using natural gas water heaters, the fuel’s cost translates into a considerable energy expenditure for the same function. Small changes in hot water habits can lead to noticeable reductions in a home’s total energy bill.
Simple Ways to Reduce Water-Related Electricity Use
Consumers can significantly reduce the municipal and residential energy burden by focusing on two areas: reducing overall water flow and minimizing the need for heating. Simple behavioral changes immediately reduce the energy needed for utility pumping and distribution. Fixing leaks promptly prevents the loss of water that has already been pumped and treated.
Installing water-efficient fixtures is an effective strategy, as low-flow showerheads and faucet aerators reduce the volume of water consumed without sacrificing pressure. This lower flow reduces the demand on both the municipal pumping system and the home’s water heater. Using a dishwasher only when fully loaded maximizes the energy and water used per cycle.
To address the high cost of heating, homeowners can lower the thermostat setting on their water heater to 120 degrees Fahrenheit. This action can save up to 5% in energy costs for every 10-degree reduction. Washing clothes in cold water is particularly effective, since over 90% of a washing machine’s energy consumption is dedicated to heating the water. Taking shorter showers also directly limits the amount of hot water the heater must supply, leading to immediate energy savings.